Free-electron masers with Bragg resonators
Botvinnik I. E. , Bratman V. L. , Volkov A. B. , Ginzburg N. S. , Denisov G. G. , Kol'chugin B. D. , Ofitserov M. N. , Petelin M. I.
Application of highly selective open resonators, based on resonant scattering of waves by corrugated metallic walls, allowed realizing efficient ("high-current") free-electron masers: the ubitron and, for the first time, a maser based on the cyclotron autoresonance.